Direction signal circuit



June 15, 1943. A R. N. FALGE ETAL DIRECTION SIGNAL CIRCUIT Filed Aug. 2,- 1940 l s Sheets-sheet 2 l veis/vr Fea/vr l alefcT/o/v Snnentors June 1.':", 1943. R, N FALGE; TAL 2,321,803

I DIRECTION SIGNAL -CIRCUIT Filed Aug. 2, v1940 3 sheets-sheet s k 5 m Q Q -1 u @anys Gttomegs Patented June 1,5,

DIRECTION SIGNAL entourrr Robert N. Falge, George W. Onksen, Jr., and 1 Howard Slone, Anderson, IInd., assignors to- General Motors Corporation,| Detroit, meh., a corporation of Delaware Application August 2, 1940, Serial 190.349,83@ 2 anims. ici iii-337) This invention has to do with e 'direction' signal especially designed for use on automobiles. it is an improvement on the type of system described and claimed in Bell Patent No. 2,122,508 granted July 5, 1938, in which stop lights atthe iront and rear of the car which are energized when the brake is applied are also employed for direction signals by flashing the stop lights on the side toward which the turn is beingmade; and in which the stop lights on the other side are caused to burn steadily when the brake is applied.

According to the present invention stop lights are provided at the rear of the car only and special lamps or special filaments are provided at the front oi the car for use as direction signals only. This reduces the drain on the battery .without substantial impairment of signaling since stop signals are of little use at the front of the car. The front direction signals may be brought into action either by suitable switch arrangements or by the use of relays or the like.

Another improvement consists in cutting out the usual taillights when the direction signals are actuated. By cutting out the tail lights the flashing-l of the direction signalY is 'made more distinct because of greater contrast. A

Other features of the invention will be pointed out in the course of the following description taken in connection with the accompanying drawings in which: Y

-Figure 1 is a diagrammatic view showing the preferred form of direction signal system.

Figure 2 is the same as Figure 1 but shows the consist of one of the laments of a two lament. bulb. For example, it will be found convenient in thecase of the iront lights to combine in-one bulb a low caudlepower parking nlament with a high candlepower direction signal la.- ment. the four corners of the car, preferably in the fenders. It will be found desirable in the case of the front lights to mount them some distance from'the headlamps to give'better contrast.

There 4is indicated on each of the gures a brake switch, this being the usual stop light switch operated mechanically, hydraulically or otherwise from the brake pedal so as to give a signal when the brake is applied. Y

There is also shown in each figure a pilot lamp warning ,which may be mounted on the dash adjacent the driver. The pilot is preferably flashed during the operation' ofy the direction signal to inform the'driver` that the signals are working properly.

The flasher shown in Figures -1 and' 2 is preierably of the construction described in detail in copending 'application of Falge and Onksen, S. N. 159,219, led August 16, `1937, which has matured, into Patent No. 2,282,956, dated May i2,A

1942. 'Ihe ilasher'is shown schematically as consisting' of an armature lil normally held in engagement with contact I2 by the tension of expansible wire IQ.. As current, checked to anappropriate extent by the resistor I5, iiows through the wire I4 it is heated and expands, permitdirection signal switch in position to indicate a left turn.

Figures 3 and 4 show a modified form of system embodying a rotatable control switch, Figure 3 showing the direction signal switch in off position and Figure 4 showing it in position to indicate a left tum.

. Figure 5 shows a further modification employving relays toenergize the signal lights as stop lights.

Figure 6 shows a. furthermodiflcation employing a plurality of nashers.-

Figure 7 illustrates a suitable form of ilasher which may be used with the circuits o f Figures 3 t0 6 inclusive. are indicated by the same reference characters. Y Figure 8 shows a modification oi the circuit of Figure 5. y

0n allthe gures the signal lightsare indicated as right front, right rear, left'iront and left rear. These signals may consist of incandescent lamps having a single filament or may In all of the iigures-flike parts ting the armature In to break-its engagement with contact I2 and to engage contact i6, armature Ill being spring-biased toward contact I6. As wire I4 is now short-circuitedfthere is no current ilowlng through it and it soon cools, contracts and lpulls armature Ill away fromy contact I6 intoengagement with contact I2. Bythis arrangement an interrupted current is supplied alternately to each of the output terminals I8 and 20 of the ilasher. In order to insure a quick break and minimize arcing at the contacts vthe hold armature II) engaged with contact I6 and to quickly lrelease the armature when thejtension of wire, I4 becomes l`suillciently great. The pilot lamp lis connected between outputr terminal I8 and the Ainput terminal 22 so that it is flashed alternately with the signal lights supplied with' current through terminal I 8.

The direction signal switch of Figures 1 and 2 is illustrated as a simple reciprocatingl switch having 'a neutral position, a right turn position and The lamps may be mounted as usual ata left turn position. It is shown diagrammatically on the figures as consisting of insulated conducting segments 24, 28', 28, 80 and 32, all of which move together and cooperate with corresponding stationary contacts as hereinafter described.

The usual tail lamps are indicated on Figures 1 and 2 as normally supplied with current 'from the battery B through the usual lighting switch, diagrammatically indicated, and conducting segment 32 when the direction signal switch is in neutral position.

When the switch is in this position current may also be supplied from the battery B to the stop lights by closing the brake switch, current then passing from the switch through conducting segment 28 to the rear stop lights. No current flows through the fiasher unless the direction signal switch ismoved to left or right indicating position for the circuits from both output terminals I8 and 28 of the flasher are open at the direction signal switch.

In indicating a left turn the direction signal switch is moved to the position shown in Figure 2.

In this position of parts, current from the bat` tery, interrupted by the flasher, is supplied from output terminal lil of the flasher through switch segment 25 to the left front direction signal light. At the same time 'interrupted current is supplied from output terminal 20 of the flasher through winding 2i and switch segment 30 of the direction signal switch to the left rear stop light. At the same time the tail lights are disconnected even though the lighting switch be closed because conthe left rear stop light are flashed; the stop light on the right side may be caused to burn steadily by applying the brake and the tail lamps are disconnected at the direction signal switch should they have been turned on at the lighting switch. During the flashing of the signal lamps the pilot lamp is also flashed.

An advantage of the circuit of Figure 2 is the1 fact that should the front direction signal lamp burn out the rear direction signal -will continue to flash for it is in series with the actuating elements of the flasher. The pilot light is illuminated only when .the direction signal switch' is closed to indicate a right or left turn and the flasher armature I0 is disengaged from contact I2 and the front signal lamp in lseries with the pilot light is in operative condition. Under these conditions the voltage drop across the pilot light is so great that the filament of the front signal in series with it is not heated sufficiently to become incandescent. Should the front signal light in series with the pilot burn out the pilot will not be illuminated since the circuit through it is thereby broken. Should the rear signal on the side toward which a turn is being indicated, burn out, the circuit through the flasher is broken and the flasher no longer operates, armature I0 remaining in engagement with contact l2, thereby short-circuiting the pilot light and extinguishing it. Consequently when either the front or rear signal light on the side toward 4which a turn is being indicated, burns out, the pilot ceases to flash, thereby indicating failure of a signal light.

In this connection it is to be pointed out that the f direction-signal lights shown at the right margin of the drawings have been denoted rear lamps, while those at the left margin of the drawings have been denoted front lamps. Such designations are employed purely for purposes of lconvenience in description and facility in under` standing and are not to be construed as words of limitation, it being manifest that the transposition vof these pairs of lamps with respect to' the front and rear ends of the vehicle would constitute no departure from the concepts of the hereindisclosed system.

In the modification shown in Figures 3 and 4 a rotatable direction signal switch is employed instead`of the reciprocating switch. The rotatable switch consists of insulated conducting segments 40,'42 and 44 which may be shifted to right or left by means of handle H. In these figures there is shown a modified type of flasher having but one output terminal 48. The flasher may be of the construction shown in Figure 7 in which current from the battery is supplied to stamping 48 to which is secured armature 50 tensioned to normally engage contact 52 but restrained by expansible resistance wire 54 connected as shown to terminal 52 and thence to solenoid 58 wound around stamping 48 and output terminal 48. Stamping 48 also carries a second armature 58 adapted to engage contact 80 connected to the pilot light when the solenoid 58 is energized. In

the position of parts shown in Figure 'l the flow of current through solenoid 58 is cut down by the resistance 54 so that it is unable to pull the armatures 50 and 58 into engagement with their respective contacts 52 and 88 but the flow of current is suiiicient to heat the wire 54 causing it to expand until armature 50 engages contact 52 thereby short circuiting the wire 54 and increasing the flow of current through the solenoid so it is able to pull up armature 58 thereby energizing the pilot lamp. This iiow of current is also sumcient to energize the signals. In the delscription of the circuits of Figures 3 to 6 it will be sufficient to bear in mind that'the flashers have but one output terminal 46 functioning on the direction signal lamps, the other output terminal 88 energizing the pilot only.

The circuit shown in Figures 3 and 4 operates as follows: In the position of parts shownin Figure 3 the flasher is inactive since its circuit is broken at the direction signal switch. When the brake switch is closed current flows from the battery B through the brake switch and thence through insulated segment 42 to the left rear stop light and through insulated segment 44 to the right rear stop light.` Upon movement of the direction signal switch to the position shown in Figure 4 to indicate a left turn, interrupted current is supplied from output'terminal 48 of the flasher through insulated segment 44 of the direction signal switch to the left rear stop light and through insulated segment 40 of the direction signal switch to the left front light. If the brake switch is closed in the position of parts shown in Figure 4 steady current then flows through insulated segment 42 of the direction signal switch to the right rear stop light. The pilot light of course is flashed so long as the flasher is in operation.

It is believed that the modification shown in Figure 5 may be sufficiently described by giving its u accuses 3 solenoids 60 and 62 are energized, thereby pulling down relays 64 and 66 and closing paths for the supply of current to the left and right stop lightsy respectively. The closing of the direction signal switch for right or left turn indication supplies interrupted current to the front light and if the brake switch is open. to the stop light on the same side of the vehicle only. If the brake switch is closed both stop lights are supplied with steady current through the operation of the relays. The pilot light of course functions as .long as the flasher is operated, with the brake switch open.

In the modification shown inFigure 6, two flashers are employed as well as two relays. With this circuit it will vbe evident that with the direction signal switch in neutral position, closing of the brake switch willk supply steady current to both of the rear stop lights. With the brake switch open and the direction signal switch thrown to right or left, interrupted current is supplied directly to right or left front direction signal, at the same time steady current is supplied to relay ld or relay l2 causing it to pull down its armature 'it or 'it thereby closing a circuit for the supply of interrupted current from the output terminals tt of one or the other of the flashers to Ieither the right or left stop signal as determined by the direction signal switch. The closing of the brake switch when the direction signal switch is in indicating position causes in connection with the similar arrangement of Figures l. and 2.

We claim:

-1. An electrical signalling system for vehicles, comprising: a right rear lamp, a left rear lamp, a right'front lamp, a-left front lamp, and a pilot lamp; a common source ofwelectrical energy applicable to all and capable of energizing any of said lamps, a two-branched conductive circuit for -feeding either the right front or the left front lamp from said source, a second two-branched steady current to be supplied to the stop signal Aon one side only of the car for the circuit to the other stop signal is broken as the result of energization of electromagnet l@ or 'i2 by the operation of the direction signal switch.

Figure l may be eliminated so that the tail lamps will be on continuously when the lighting switch is closed. Various other modications will occur to thoseskilled in the art.

The modification shown in Figure 8 is an improvement on that shown in Figure 5. Itis believed that this circuit likewise will -be made clear by a description of its operation. Here the direction signal switch is of a double-throw double-pole type. When the switch is in neutral position closing of the brake switch operates through the relays to pull down armatures closing circuits to the rear lamps causing them to burn steadily as stop lights. When the direction signal switch is thrown to either left or right position interrupted current is supplied from the asher to the front and rear signals on the side determined by the position of the switch. Should the brake switch and the direction signal switch be closed at the same time the rear lamps will bum steadily and the front lamp on the side toward which the turn is to be made will ash but the pilot lamp will be out since its circuit is broken at the relay. This will probably not be a serious inconvenience as the brake switch is normally closed but a short time. The-pilot, of course, will properly indicate failure of either front or rear lamp when the brake switch is open as explained conductive circuit for feeding either the right rear or the left rear lamp from said source, an electrically-operated automatic asher switch having its intermittent-contact actuating-.mechanism-series-connected into the trunk of one of said conductive circuits for energization by current now therein and for periodically interrupting the continuity of said current flow to the selected lamp thereof and to itself, a circuit interlrupter in series with the trums of the other conductive circuit, said circuit interrupter being actuated by the contact-actuating mechanism of said flasher switch to periodically interrupt current now in said other conductive circuit at the same frequency but in opposite phase to the interruption of current in the asher-energizing circuit, a third two-branched conductive cirl cuit having both branches jointly controlled by a brake-operated switch for steadily feeding each of said rear lamps from said source to indicate vehicle-brake operation, a master switch having selectively-associable contacts located in each branch of said rst and second conductive circuits and conjointly pcsitionable to enable only the alternate intermittent energization of both right lamps, or of both left lamps, or of neither, and having contacts in each branch of said third conductive circuit shiftable conjointly with the recited selective positioning of said first-circuit and second-circuit master switch contacts respectively to open the third-circuit branchfeeding the left rear lamp, to open the branch circuit feeding the right rear lamp or to open neither' of said third-circuit branches, and circuit means right pair of lamps or the left pair of lamps areA `individually intermittently energized in opposite phase.

2, An electrical signalling system for vehicles, comprising: a right rear lamp, a left rear lamp, a right front lamp, a leftfront lamp, and a pilot lamp; a. common source of electrical energy applicable to all and capable of energizing any of said'larnps, a two-branched conductive circuit for feeding either the right front or the left front lamp from said source, a second two-branched conductive circuit for feeding either the right rear or the left rear lamp from said source, an electrically-operated automatic asher switch having its intermittent-contact actuating-mechanism series-,connected into the trunk of one of said conductive circuits for -energization by current iiow therein and for periodically interrupting the continuity of said current flow to the selected lamp thereof and to itself, a circuit interrupter in series with the trunk of the other conductive circuit, said circuit interrupter being actuated by the contact-actuating mechanism of said iiasher switch to periodically interrupt current flow in said other conductive circuit at the same frequency but in opposite phase to the interruption of current in the flasher-energizing brake-operated switch for steadily feeding each,

of said rear lamps from said lsource to indicate vehicle-brake operation, a master switch having selectively-associable contacts located in each lamp, a conductor directly connecting one terminal of said source of electrical `energy to one terminal of said pilot lamp, a second conductor branch of said iirst and second conductive ciry cuits and conjointly positionable to enable only the alternate intermittent energization of both right lamps, or of both left lamps, or of neither, a d having contacts in each branch oi said third onductive circuit shiftable conJointly with the recited selective positioning of said first-circuit and second-circuit master switch contacts respectively to open the third-circuit branch feeding the le`i't rear lamp, to open the branch circuitfeeding the right rear lamp or to open neither of said third-circuit branches, and a circuit for ilashing said pilot lamp when but only when the right pair of lamps or the lett pair of lamps are individually intermittently energized in opposite phase, said last circuit consisting of said pilot connecting the other terminal of ysaid pilot lamp to the rtrunk of one of said two-branched circuits controlled by the first-recited selector contacts oi.' said master switch, electrically conductive means periodically brought into shunting relation with said pilot lamp by said flasher-switch actuating mechanism during a portion of each cycle of flasher-switch operation, and electrical resistance in that portion of said circuit which is periodically shunted out by said last-mentioned means, said electrical resistance havin'g a value such as to limit current flow in the circuit, unshunted, to an amount insuiilcient to effect perin series therewith.

ROBERT N. FALGE. GEORGE W. ONKSEN, JR. HOWARD I. SLONE. 

